5000 USD seems high to me as well for a student and you don't know what his girlfiend does. It does not really matter how high that amount as long it can cover unexpected expenses.
When I was a student, I made sure I always had at least 1000 EUR on my account, basically treating the 1000 as 0. I cannot remember ever running into debt this way.
with savings, a personal and a additional 5k usd checking account... sry to burst your bubble but thats called wealthy for most ppl on earth.